Pneumatic tire.



l. J. WEBSTER.

PNEUMATICTIRE.

APPLxcAnoN man mm, 1913.

, Patented Nove 2, 1915.

VVnnesses @iX/@Mw UNITE@ Strafen@ raffinare @einen IRA WEBSTER, OF HAVERHILL,

MASSACHUSETTS, ASSIGNOR-TO RELIANCE A. C.

COMPANY, INC., 0F NEW YORK, n. Y., A CORPORATION or NEW YORK.

PNEUMATIC Specification of Letters Patent.

Patented Nov. 2, 191152 Be it known that l, lim fl. lVniss'rnu, a eitizen oi' the United States, residing at llaverhill, eniint'v ot' Essex, Statfe ot' lilassaehiisetts, have, invented an linproveinent in lneninatie Tires, of which the following description, in eonneeti'on with the ari-.oinpanyingdrawing, is a. speeiieation, like eharaeteri4 on the drawing representing like parts.

This invention relates to pnenniatie. tires ot' that type in whieh the riihher at 'the tread portion ot' the tire is held iinder'a severe eoinpi'ession when the tire is inflated so that it' a punrtiire oeeura the severe eompressioniinder which the tread is held will iininedialely elose iip the piiiietnre and prevent the eerape of air. In United States Patent No. 981,208," granted to Donnell on January 10, 1911, an inner tube for a pneumatic tireI having the above-deserihed features is shown. ln the lire shown in this patenttlie ruhher of theI tread portion is held in its eonipreSSed condition h v a stay-Strip which is applied to the tread portion of the tire during the inanulaetiire thereof and whieh is eonstrugted so as to prevent. any transverse expansion. 'l`hi.\` stay-strip in the. patented devieeis on they exterior ol' the inner liihe and eonseipiently when the tire is used it eonies in eontaet, with the inner 'fare ol' the. shoe. l lind that thisiS a detriment heeaiise diiiine' iise there is apt to he a slight movement. heweeii the inner face of the shoe and the inner tiihe which results in wearing and eonseiiueiitiy weakening the stay piece. Sui-h wearingr or weakening if allowed to proceed will eaiise the, stay strip toilose its strength thereby permitting the riihher to expand to siii-h an extent to prevent it iroin antoinatieallv eloxing' up a puncture. ln order to prevent this l have provided a eonstriietion wherein the latayntril-i is protected from heilig' worn by eontaet with the shoe.

My invention also provides a novel conslrnetion whieli eliminates any weakness at the, sides of the inner tiihe adjacent the edge oi' the stay-strip, and votherwise improves pnenniatie tires` ol' the ahove nature, all as will he. iiioi'e fully hereinafter described and then pointed out in the appended claims.

Referring to theI drawings wherein l have illustrated the preferred emhodiment ot' in y invention7 Figure 'l is a cross-sectional view showiner one oi' the first steps in the manni'aeture ot' in v improved tire: hij. 2 is a eross-seeiional view showing the. tire aft-er ha ving heen reinoved 'ii'on'i the eore and heinl;r tiii'neil right side ont: Fig. 3 is a crosssertional view showing: the inner tube inflated and in positionA within the outer Shoe; lFigi. vl in a side, view ot a portion of the inner tiihe inilaien; Fig. Si in a view showing the torni oi' `av-Strip whiehi` pi'el'er t0 ernplo As stated ahove in)Y invention is partieiilarly applieahle to inner tiihes and in Figi. Ii l have Shown at 1 an inner tiihe einhodvingA iiijcinvenion whieh is Situated within an outer ihoe or easing 3. in in)r iinproveil inner tnhe the ruhher of the tread portion i is held niider severe. eonipression in a li'aiisverhe ilireetion hy ineans of a `stay-strip -i whieh ia inwirporated in the inner lnhe. ln niakiner the inner tube l propose i'o inake it. wrongf side ont on a mandrel i, as shown in Fig. 1, said'inncr tuhe heiner inade with the thiekened tread portion 2i.

In making: the lire i employ a Stay-strip -i' oi eanvas or other similar inaterial and, einhed this Stay-strip in the tread portion of the tire adiaeentthe nianilrei in lmeh a wayas to leave a small anioiintot riihher (i hetween the slay-:strip and thenianiirel. i proposeto inake the innertiilieinseelionxeaehofwhich is if siillieient length so that hy eeinenting iog'eiher the enila1 thereo' a eoinplete. inner tiihe ean he iornied and the .atirv-atripli for eaeh inner iiihe extends; the, iiill length of the seeiion or length 'l'roin which the inner tiihe is niade. Vr'hen the tire is matie as shown in iiigf. 1, the riihher comprising the inner tnhe, and the wtiiv-si'zrip #l are. in their norinal rendition and are not under internal s'rain. ili'ter a section of inner tube has heen properly niaile and iuicanizceil the core 5 in removed and then this section of tire is turned inside out in :i inannei` similar to that in whieh a stoeking is tiirned inside ont. This turning ot' the inner tnhe section in side ont brings the fai-.e i' which is on the interior et the tuhe iii Vig. 1 on the exterior thereof and hriue'a the face 8 which is on the exterior 'of the tiilie in Fig. 1 0n the interior thereof as'shown in Fig. 2.v The staynstrip #l is; ineapahle oi stretching'in n transverse direction` and this tin-niner o f the tube inside out results in subjecting the rnb iininci'liatrlv at the point ber 3 of the tread to a considerable compression, as will be obvious. lUhen the tube iS first turned inside out it will have the cross sectional shape shown in Fig. 2, but ,when 't is inliated, as shown in Fig. 3, then the bringing of it into this shape 'will increase the compression transverselyT under which the rubber of the tread is held. I should here remark tl after turning' inside out the section of tubing; from which an inner tube is to be made the ends of the section are jointed together in some suitable Way so to make the complete inner tube.

-By incorporating the staystrip 4C in the rubber and providingr thelayer t5 of rubber on the exterior of the stayst1ip, it will be seen that when the inner tube is inserted into the shoe 2 the stay-strip will not have any contact with the inner 'face of the. shoe and will not, therefore, be weakened by wear.

i 'In making my inner tube l propose to make the .stay-sirio of such a width that the edges ot' tlic stay-strip come at about the sides oi the inner tube when the latter inflated, as clearly seen in the drawings. While it is important that the tread surface of the inner tube should not expand but should be held under compression, it is desirable that the ,inner portion 9 of the inner tube should be capable Aof expanding in or?y der to permit the .inner 'tube to completely till the shoe when the tire is inlh. and also to permit cross-sectional expansion of the lire as a whole. My inner tube. therefore, is one havingr a thickened tread and provided with a stay-strip covering the portion of' the iread exposed to puncture and holding such portion in compression, sai'diiiinrr tube haviin;r the integral part thereof between the edges of the stay-strip unrestrained o r unsta-yed to permit cross-sectional expansion of the tire.

l have Jfound from experiment that where the stay-strip' l has a straight edge the in nei' tube is api. to break first at edge of the stay-strip- This is part because when the stay i abrupt change from the "tryed 'to the unsiayed lpnrtion ot the rubber produces :i condition that "en the tube .ind` the lgreater exp nn-'tion of the rubber ten-'ls to take place of junction between he stared and unstali/ed noi-tions or at the ol' the stay-strip, and when there in ihr: a greater expansion at this point the strength ol'lhe inner tube is correspondinglv weakened atuci: point. lvioieover, when 1hr, lire is in use the w'eigijht of the antoniobie tends to .flatten that portion ol it which rests ou this ground and this flaiteui tends o causian outward bulge ai. thc les ol the liiv. This outward thrust or bulge taires bl: :e ai. the point where the stajveil and un ed portionsI oiA the inner tube joui and or progressi vely-increused strip is thus made with a straight edge sien ci' the unstayed.

ivear between the shoe and theiinner tube at the* sidesbf the latter, which wear would come at substantially the line of junction between the vstayed and unstayed yortions'of the inner tube. The occurrence o such wear tends to still further weaken the inner tube at this point. In order to overcomethisobjection and to provide an inner tube which will be free therefrom I propose to make the stay-strip with edges having gradually so that, there will be a gradual blendin from the stayed to the unstayed portion o the tire. One construction of stay-strip having these qualities is shown in` Figs; 4 und 5 wherein the 'edge of the stay-strip is serrated and provided with. the taperin7 projections 10. W ith a construction like this the staystrip will have its maximum stayingqualities along the line 1l and its minimum stayimg qiialities along the line 12 in Fig. 4, and

at intermediate points the 'stay-strip will have progressively-iuci-ease staying pro1p-` f,

erties from-the line 12 taff(H he line 11. therefore, in the manufacture of thev there is a weak spot in the rubber along some intermediate line, such as the line 13, the projections will reinforce the rubber at this point sufficiently so that it will not be subjected to an undue strain sufficient t0 cause a rupture. This construction whereby there is a gradual change from'the stayed to the unstaycd portion of the tire/makes a construction which is free fromi the objections above noted and which gives excellent satisfaction. in use.

My invention, of course, is not limitedl to the l. particular shape of stay-strip herein ilh/istrated asany construction which will give this gradual blending from the stayed to the unstaycd portion of the tirewould come within my invention.

I will preferably .use a stay-strip which is cut/on the bias, as shown in Fig. 5.

' Having fullv described my invention, what 1 claim as new and desire tofsecureby Letters Patent is:- f

l. f An inner tube For' la. pneumatic tire having.y a thickened treed portion of rubber which ,fis highly compressed in a transverse direc, ,in and av stay strip' associated Iwith Moreover, 'this continual flattening of the tire causesmore or lesa.

stayingproperties tire stayed and ihe unstayed portion/ol' the inner lubrin which the stayiiigrcl'lect ispi'ogrcsol' coiiipie, on in a transverse direction, an

iscv

mame/ec 3 unstuyed portion opposite the bread pm'ton, in testimony whereof, I have signed my und nu mtermedmte portlon on each side of name to tins speclcatxon, 1n the presence'of the rn'e between the stayed and the 'nasi-eyed two subscmbmg wltnesses.

portions, which intermediate pmon is pro- IRA J. WEBSTER. vlded mth smymg means having u progres- YWltnesses: y slvely-lnerense staying effect tem the un LOUIS C. SMITH,

sdyed te the stayed pur-ion. BERTHA F. HEUSEP 

